Should You Worry? Petrol in a Diesel Car in Newfield
Probably less than you are now — provided nobody has started the vehicle. Everyone around Newfield starts with "have I ruined it?", and the honest answer is generally no: petrol left inside the tank of a diesel stays harmless till priming, cranking or driving pulls it into the fuel system. Leave your motor off and ring Petrol in Diesel — that keeps it that way. Read on for three things: the effect petrol has inside a diesel motor, the signs of how far it has spread, and the way to make sure you never do it again.
The motor and petrol in a diesel: what happens
Passing through a motor, diesel is doing two things at once. It burns, and before it burns it protects. The high-pressure fuel pump and the fuel injectors are designed to very fine gaps, and the diesel passing through them is what keeps those surfaces from wearing against each other.
The second job petrol does not do at all, and the first it does poorly. A pump running on a petrol mix is wearing itself out, since petrol is runnier than diesel and strips out the lubrication your fuel system depends on. Petrol is also designed to resist igniting under compression — the reverse of what a diesel needs from its fuel — and that is where the clattering starts.
Seen together, they show what shape the trouble takes. Contact doesn't do the damage — movement does. A tank with petrol in it is a fuel issue. The start of a mechanical problem is a pump that has been running on that petrol — and whatever a worn pump sheds moves on with the fuel to the injectors downstream.
How bad is petrol in a diesel? Four scenarios our engineers see around Newfield
Filled but not once started — the best it gets. At a forecourt, and genuinely only there, the petrol is still limited to your tank — because everywhere else the car was driven to get to it. The job is emptying and flushing on the spot.
Started for a moment, or only your ignition on. Your system has been primed, so petrol has left the tank and got to the fuel filter and your lines. Usually little more than clearing, cleaning and sorting the fuel filter, and so still simple.
The pump has worked a couple of miles on weakened fuel — that's what driving the car meant. Miles is only half of it; how hard it was driven matters equally. Either way the work runs to that tank, the lines, your filter and fresh fuel through the entire system. On the school run to Roseberry Primary and Nursery School, the mileage is small. Very different once more: a run to Durham, under 10 miles away, or any distance on the A1(M), under 3 miles from Newfield, where your engine never stopped running hard.
Rattling, an uneven idle, smoke, a throttle gone soft: driven until it complained. That's the engine telling you its fuel has stopped acting like diesel. Leave it where it has stopped: a lay-by, a quiet street, the verge on South View. Long-term damage is very rare if a vehicle is pulled over soon, and the fuel drain and flush that still go first take care of it.
Myths Newfield drivers hear about petrol in a diesel
Myth: "Fill it the rest of the way with diesel and it will be fine." It will not. Topping up takes out nothing; it gives you a bigger tank of the same mixture. Percentage isn't how a diesel fuel system tolerates petrol, whatever that guidance assumes.
If anything, the opposite is true. Myth: "A modern diesel can cope with a bit of petrol." Smaller components and higher pressure are how a newer diesel runs its fuel, and that makes the protection count more, not less.
"It starts, it drives, and so no harm done" — the myth that trips up more motorists than any other. A petrol engine fed diesel usually will not run, and so the motorist stops and the harm stops with them. Whilst your pump grinds, a diesel fed petrol usually starts, idles and drives away as though nothing has happened. Running is not the same as fine.
"A drop of two-stroke oil and drive it home" — a myth, taken from a fix from years ago, for a separate issue. It does not put back what petrol has weakened, and the petrol is still inside the tank after that.
"Drain it yourself and you're sorted" — a myth, since after it's been running some petrol sits in the filter and lines, ready to go right back through your pump on the next start. Draining petrol into a can by the roadside is also really risky.
Petrol in a diesel: how does it take place?
No one does it on purpose, and it's rarely carelessness. A diesel nozzle generally will not go into a petrol vehicle, but the smaller petrol nozzle goes into the filler of a diesel almost without resistance — so forecourts make this one mistake easy, and just in one direction.
It happens when habit and the vehicle stop matching. Courtesy car, hire car, or a motor that is brand new. A household with one petrol and one diesel on the driveway. A well-known forecourt with the pumps in a different order. Racing for a train at Chester-Le-Street and fuelling up en route. A new-to-you diesel Renault Megane, its first fuelling, and a motorist used to petrol: precisely when it takes place. The hand does what it has always done when you add rain, a phone call or a back seat full of children.
Next time you fill up around Newfield: preventing petrol in a diesel
- Check the petrol pump, not the colour. In the UK unleaded handles are normally green and diesel black, but not on each forecourt. The label is what counts.
- In a vehicle you do not know, look inside the flap over the filler or at the cap before your first fill: plenty of cars print the fuel type there.
- Good intentions do less than a sticker or a fob in a vivid colour on the diesel's key when a household has one of each. So mark it.
- "Diesel", out loud, before you lift the nozzle — each time a new or hired car gets its first tank. It sounds daft. It works.
- Mistakes like this are easy to make whilst your mind is on something else, and so your phone goes away.
- Some diesels have a filler designed to reject a petrol nozzle, and devices you can add exist for vehicles without one. Such an inhibitor helps up to a point — as a safety net, not a reason to stop reading the petrol pump.
- Stop as soon as you realise. Less petrol in your tank makes a thinner mix. It doesn't change what to do next, which is still not to fire it up.
Already put petrol in a diesel around Newfield?
Then the order of things is brief. Leave it unstarted, with your ignition off too. Ask the attendants to help you roll it clear of the petrol pump if you're still on the forecourt, whether that is Esso or somewhere else. Next, 0333 366 0103. We'll ask what got in, about how much, and if it's been run.
If it was AdBlue rather than petrol, say so. That's a separate fault — corrosion and deposits rather than lost lubrication — and it has its own page for Newfield.
Newfield petrol in a diesel jobs: why one costs more than another
A fair single price doesn't exist here: four situations, four separate tasks. The situation itself does most of the work of moving your cost. Where your car is matters too, and whether a van can safely reach it, after the proportion of petrol to what your tank takes.
That's why our technicians ask three questions before pricing rather than after: what got in, how much, and whether it's run. The answers change a range into a straight figure.
About Newfield itself
Newfield is a village situated on the riverside in County Durham, with a population of around 1213 people. Newfield has a mix of housing types, but terraced houses are the most predominant. Newfield is located near several other small settlements, including Pelton Fell, Whitehill, and Grange Villa, and is approximately 6.2 miles from the city of Durham. Newfield sits at an elevation of 95 metres above sea level, in the north east of England.
Fuel drain cover across Durham, Newfield included
Newfield sits in the DH postcode area, and the teams that answer petrol in diesel calls there work the locations near it as well — Pelton Fell, Whitehill and Grange Villa among them. No need to move your vehicle to us. Forecourts, supermarket car parks, lay-bys and your own driveway are all places we drain.
At the petrol pump in Newfield, right now?
Then you're in the best spot there is. Ring, and keep it turned off.